<MyGrid>:  #do with the MyGrid class
    # variables
    name: name  #global variable, poit to the id "name"
    email: email

    GridLayout:
        cols: 1
        size: root.width - 200, root.height - 200  #control the expand
        pos: 100, 100 #change the position

        GridLayout:
            cols: 2

            Label:
                text: "Name: "

            TextInput:
                id: name
                multiline: False

            Label:
                text: "Email: "

            TextInput:
                id: email
                multiline: False

        Button:
            text: "Submit"
            on_press: root.btn()  #root: look for the function, it'll pass an instance to the method